RESUMO
Eliminating facial electromyographic (EMG) signal from the electroencephalogram (EEG) is crucial for the accuracy of applications such as brain computer interfaces (BCIs) and brain functionality measurement. Facial electromyography typically corrupts the electroencephalogram. Although it is possible to find in the literature a number of multi-channel approaches for filtering corrupted EEG, studies employing single-channel approaches are scarce. In this context, this study proposed a single-channel method for attenuating facial EMG noise from contaminated EEG. The architecture of the method allows for the evaluation and incorporation of multiple decomposition and adaptive filtering techniques. The decomposition method was responsible for generating EEG or EMG reference signals for the adaptive filtering stage. In this study, the decomposition techniques CiSSA, EMD, EEMD, EMD-PCA, SSA, and Wavelet were evaluated. The adaptive filtering methods RLS, Wiener, LMS, and NLMS were investigated. A time and frequency domain set of features were estimated from experimental signals to evaluate the performance of the single channel method. This set of characteristics permitted the characterization of the contamination of distinct facial muscles, namely Masseter, Frontalis, Zygomatic, Orbicularis Oris, and Orbicularis Oculi. Data were collected from ten healthy subjects executing an experimental protocol that introduced the necessary variability to evaluate the filtering performance. The largest level of contamination was produced by the Masseter muscle, as determined by statistical analysis of the set of features and visualization of topological maps. Regarding the decomposition method, the SSA method allowed for the generation of more suitable reference signals, whereas the RLS and NLMS methods were more suitable when the reference signal was derived from the EEG. In addition, the LMS and RLS methods were more appropriate when the reference signal was the EMG. This study has a number of practical implications, including the use of filtering techniques to reduce EEG contamination caused by the activation of facial muscles required by distinct types of studies. All the developed code, including examples, is available to facilitate a more accurate reproduction and improvement of the results of this study.
RESUMO
Introdução: Sinusite é uma doença de base inflamatória ou infecciosa que acomete os seios nasais, aumentando o volume da mucosa e obstruindo a sua comunicação com as fossas nasais. A aplicabilidade da drenagem linfática facial visa eliminar o edema e aliviar sintomas dolorosos. Objetivos: Analisar a qualidade de vida (QV) e a dor antes e após a drenagem linfática facial em indivíduos com sinusite. Métodos: Ensaio clínico randomizado, quantitativo e intervencionista realizado com 22 indivíduos com sinusite. Foram realizadas dez sessões da técnica, método Leduc. Utilizaram-se os instrumentos WHOQOL-BREF e a Escala Visual Analógica para avaliação da QV e do nível de dor, respectivamente, antes e após as sessões. Os dados obtidos foram analisados no programa SPSS 18.0. Resultados: A idade média foi de 28,14 ± 10,283 anos, 68,2% eram mulheres e 31,8% homens. O escore de QV geral foi de QV 57,44 antes, e 64,53 após. Na comparação dos escores de QV antes e após verificou-se diferença estatisticamente significante entre os domínios físico (p=0,000); psicológico (p=0,000) e meio ambiente (p=0,000). Quanto ao nível de dor também houve uma melhora estatisticamente significante (p=0,000). Conclusão: Através dos resultados pode-se concluir que a intervenção fisioterapêutica foi efetiva no tratamento da sinusite. (AU)
Introduction: Sinusitis is an inflammatory or infectious disease that affects the sinuses, increasing the volume of the mucosa and obstructing its communication with the nasal passages. The applicability of facial lymph drainage aims to eliminate edema and relieve painful symptoms. Objectives: To analyze quality of life (QOL) and pain before and after facial lymph drainage in individuals with sinusitis. Methods: Randomized, quantitative and interventional clinical trial with 22 individuals with sinusitis. Ten sessions of the technique were performed, Leduc method. The WHOQOL-BREF instruments and the Visual Analogue Scale were used to assess QOL and pain level, respectively, before and after the sessions. The data obtained were analyzed in the SPSS 18.0 program. Results: The mean age was 28.14 ± 10.283 years, 68.2% were women and 31.8% were men. The overall QOL score was 57.44 before, and 64.53 after. In the comparison of the QOL scores before and after, there was a statistically significant difference between the physical (p = 0.000); psychological (p=0.000) and environment (p=0.000) domains. As for the pain level, there was also a statistically significant improvement (p=0.000). Conclusion: Through the results it can be concluded that the physiotherapeutic intervention was effective in the treatment of sinusitis. (AU)